1 | /* Store current floating-point environment and clear exceptions. |
2 | Copyright (C) 1997-2022 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <fenv.h> |
20 | #include <unistd.h> |
21 | #include <ldsodefs.h> |
22 | #include <dl-procinfo.h> |
23 | |
24 | int |
25 | __feholdexcept (fenv_t *envp) |
26 | { |
27 | /* Store the environment. Recall that fnstenv has a side effect of |
28 | masking all exceptions. Then clear all exceptions. */ |
29 | __asm__ volatile ("fnstenv %0; fnclex" : "=m" (*envp)); |
30 | |
31 | /* If the CPU supports SSE we set the MXCSR as well. */ |
32 | if (CPU_FEATURE_USABLE (SSE)) |
33 | { |
34 | unsigned int xwork; |
35 | |
36 | /* Get the current control word. */ |
37 | __asm__ ("stmxcsr %0" : "=m" (envp->__eip)); |
38 | |
39 | /* Set all exceptions to non-stop and clear them. */ |
40 | xwork = (envp->__eip | 0x1f80) & ~0x3f; |
41 | |
42 | __asm__ ("ldmxcsr %0" : : "m" (*&xwork)); |
43 | } |
44 | |
45 | return 0; |
46 | } |
47 | libm_hidden_def (__feholdexcept) |
48 | weak_alias (__feholdexcept, feholdexcept) |
49 | libm_hidden_weak (feholdexcept) |
50 | |